Suntan = healthy is a big mistake! A doctor explains the amazing damage that ultraviolet rays do to your skin and whole body
The image that “tanning is healthy” is actually a dangerous benefit. Sunburn is a “sign of damage” in which the skin desperately protects energy from ultraviolet rays. Not only does staining increase the risk of wrinkles, but it can also cause skin cancer and affect your overall health. Children’s skin is particularly sensitive to UV rays, which can lead to future risks. Mr. Yuemura from CLINIC explained it to us.
Supervisiondoctor:
Kimiyuki Koemura(first clinic)
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After graduating from Kitasato University School of Medicine, completed initial training at Kitasato University Hospital. After that, he joined the Department of Neurosurgery at Kitasato University Medical Center, where he engaged in emergency medicine and treatment in the new coronavirus infection ward. From 2022, he gained medical experience at a major cosmetic surgery clinic, and in 2023, he joined “THE FIRST CLINIC” and became the director. Full member of the Japanese Society of Neurosurgery. He is also conducting joint research on perovskite solar radiation with Project Professor Tsutomu Miyasaka.
What is sunburn? The effects of ultraviolet rays on the body and how it turns black
Editorial department
Please tell me what happens inside your body when you get a sunburn.
Mr. Karemura
Sunburn is the body’s defense response to UV radiation to protect the skin’s DNA. UV rays have high energy and directly damage the nuclear DNA of skin cells. To counter this, melanocytes produce melanin, which absorbs and diffuses ultraviolet rays to protect cells. When this melanin appears on the skin surface, the skin appears dark.
Editorial department
There are different types of ultraviolet rays, but how do they affect the skin?
Mr. Karemura
The ultraviolet rays that reach the earth’s surface are mainly UVA and UVB. UVB has a strong effect on the epidermis, causing redness and inflammation (sunburn). UVA rays are long-lasting and reach deep into the dermis, destroying collagen and elastin, causing wrinkles and sagging skin. UVA also passes through window glass, so it continues to affect you indoors and inside your car.
Editorial department
Please tell me more details.
Mr. Karemura
UVA to UVB photon energy is approximately 3.1 to 4.4 eV (electron volts). This is the theoretical value required to electrolyze water to separate it into oxygen and hydrogen (1.23) In fact, this energy also degrades plastic. For example, if you leave a plastic bag outdoors, the molecular bonds will be broken by ultraviolet rays and it will fall apart in a few years. Just imagine that the same damage is happening to our skin.
Editorial department
Tanning is sometimes said to be healthy, but how is it considered medically?
Mr. Karemura
“Dark skin = healthy” is a popular cultural image. Medically, sunburn is obvious skin damage. 10 to 15 minutes of sunlight a day is enough for vitamin D production, and there are few additional health benefits.
What’s wrong with getting too much sun? Effects on the whole body, not just skin aging
Editorial department
What are the negative effects of getting too much sun on your skin?
Mr. Karemura
In the short term, redness, pain, and blistering (a type of blistering) may occur. In the long term, melanin production and distribution are disrupted, leading to an increase in age spots and freckles. Additionally, deep wrinkles and sagging progress due to collagen destruction caused by UVA. For example, if you are a truck driver, deep wrinkles and stains are concentrated on the face (feelings) facing the window, which is clearly compared to the inside of the car (on the right side). This is proof that UVA penetrates glass and causes instant damage over several decades.
Editorial department
Do you agree with the idea that UV rays can have an impact on the health of the entire body?
Mr. Karemura
yes. UV radiation is a major environmental priority for skin cancers (basal cell carcinoma, squamous cell carcinoma, malignant melanoma, etc.). It is said that the risk increases especially if you have been exposed to strong sunburn since childhood. It has also been reported that resistance to infectious diseases temporarily decreases because it suppresses immune function. The effects of cataracts are severe and have been established as one of the causes of cataracts, which cloud the crystalline lens. If humans become immortal, if we continue to be exposed to ultraviolet rays without protection, we will definitely develop cataracts. This is because, just like the skin, if the eyes are exposed to stress from UV rays for many years, irreversible damage will occur.
Editorial department
Please tell me why people with breakdowns or sensitive skin should be especially careful.
Mr. Karemura
In addition, because the amount of melanin is low, it is easy for cells to be directly damaged by UV rays. There is also data showing that even one sunburn that causes blisters during childhood increases the risk of skin cancer later in life. People with sensitive skin also need to be especially careful, as their barrier is weak and they are prone to pigmentation and rough skin after inflammation.
How to get a healthy tan? The correct way to tan and what not to do
Editorial department
What are the wrong ways to tan?
Mr. Karemura
The most dangerous thing is to sunbathe for a long time without sunscreen or only use oils that promote tanning (sun oil) with the intention of “scorching”. These maximize the risk of DNA damage and acute inflammation. Additionally, tanning salons artificially emit strong UVA rays, which has been shown to potentially increase the risk of photoaging and skin cancer even more than natural light.
Editorial department
Is there a healthy way to tan?
Mr. Karemura
The general rule is to “take necessary measures against sunlight while minimizing damage.” Please take the following precautions when going out.
1. Applying sunscreen
Please use SPF30/PA+++ or higher for everyday use, and SPF50+/PA++++ for leisure. Reapply every 2 to 3 hours, and reapply if it comes off with sweat or water.
2. Physical shielding
Wear a hat (with a wide brim), sunglasses with UV protection, and long-sleeved shirts and arm covers.
3.Select time zone
Be especially careful between 10am and 2pm when UVB is strong. Please take advantage of the shade.
Additionally, children should use hypoallergenic sunscreen (SPF 20-30 degrees), wear hats, and play in the shade.
Editorial department
If I get a sunburn, please tell me how I can take care of it myself.
Mr. Karemura
Sunburn is a mild but unsatisfactory condition on the skin. First, use an ice pack wrapped in a clean towel or a cold shower to gently soothe the hot flashes on your skin. After inflammation occurs, the skin tends to become very dry, so it is important to replenish moisture with a low-irritant, highly moisturizing lotion, emulsion, or cream. Avoid irritating things like scrubbing or scrubbing your face, and use gentle care until your skin calms down.
Editorial department summary
Sunburn is not a “health” but a “defensive response,” and beyond that, damage lurks at the DNA level. UV rays use the energy to decompose plastics, causing them to deteriorate even more than they otherwise would, creating deep wrinkles and damaging your eyes over the years. However, with the right knowledge and precautions (sunscreen, shielding, time management), the risk can be greatly reduced.
Clinic information
first clinic
| location | 4th floor, Tama Center Building, 1-9-1 Ochiai, Tama-shi, Tokyo 104-0061 |
| Medical subject | Cosmetic surgery/cosmetic dermatology |
| Medical hours | 10:00～19:00 |
| Closed days | Wednesday/Sunday |